Tamagotchi Debug Mode

I found a software debug mode in the Tamagotchi code that allows the game state to be viewed and changed in ways that aren’t normally allowed. This mode allowed me to answer more questions about Tamagotchi functionality.

The mode!

I noticed this when looking at the figure processing functionality. Each figure has a unique ID, located at byte 0x14 in the figure data, which is used by the Tamagotchi to determine how many figures have been attached, and also store related data, such as which items have been purchased. But there appears to be a special case for one ID.

FE! FE!

Loading this image onto a figure and attaching it to the device didn’t have any immediately visible effect, but once I looked at the Tamagotchi’s stats, it was clearly in a debug mode. I was able to edit the Tamagotchi’s stats in every screen (for example, make the Tamagotchi weigh more or be more or less hungry), and also change the sprite of the Tamagotchi. There was also an extra screen in stats (see above) that appeared to contain internal information about the Tamagotchi. The heart and the man icon are the two “care factors” I talked about in a previous post. The leaf and the house are two other care factors which appear to be update, but never used. Since there are also many unused characters in the Tamagotchi ROM, my guess is that these were intended to affect the growth of those characters but they were for some reason removed. The ‘X’ is the Tamagotchi’s spouse, which can also be changed. The ‘CT’ is the number of figures that have been attached to the device, which maxes out at 100. There’s a special screen that appears that you can see in the video below.

This allows me to answer a few more questions of Tamagotchi life.

Are there any secret characters in the TamaTown Tama-Go?

At this point, probably not. None of the extra characters seen in the ROM dump appear in the debug mode, and I can’t find any way to get them in the code. So it seems pretty likely they’re not available

Does it make a difference who your Tamagotchi marries?

Not as far as I can tell (so long as they don’t marry an Olditchi). I can’t find anywhere a Tamagotchi’s spouse affects it’s stats, and it definitely doesn’t affect what its child grows into.

Does anything special happen if you attach a lot of figures to your Tama-Go?

There doesn’t seem to be. They only behavior that appears to be impacted by the ‘CT’ number in the stats is the screen that gets displayed (at 100, you get the Tamagotchis dancing).

Keep the questions coming!

Don’t feel like making your own debug mode figure? You can buy one here.